1. Field of the Invention
This invention relates to a supporting structure for an operation pedal of an automobile.
2. Description of the Related Art
In general, drivers attempt to stop their cars by stepping deep on a brake pedal when they encounter an imminent crash. But in fact, many of them fail to stop the car and bump in a state of stamping on the brake pedal.
In such a case, the front part of a vehicle crushes with absorbing the energy of a crash. Its engine placed inside an engine room moves back, pushing a master cylinder of a brake unit located behind the engine. Herein, the master cylinder is connected to the brake pedal located behind a dash panel via an operating rod. Thus, the master cylinder pushes back the brake pedal via the operating rod.
As a result, there is a disadvantage in that the driver has a crash load on his foot because he is stepping deep on the brake pedal until immediately before the crash, and then receives a strong kickback, making an impact on the foot.
Conventionally, various measures are suggested to cope with such a problem. Japanese Patent Laid-Open No. 2001-138878 specification, for example, is configured by comprising: a first bracket fixed on a dash panel; a second bracket, an operation pedal being pivotally attached to the second bracket so that the operation pedal can swing, the front-end lower part of the second bracket being pivotally attached to the first bracket so that the second bracket can swing, the rear-end upper part of the second bracket being fixed on a vehicle body-side member so that the second bracket can be removed from the vehicle body-side member by an impact load at the time of an automobile crash; and a compressed spring, which is disposed in a compressed state between the first bracket and the second bracket and promotes a backward turn around the pivotally attached position of the front-end lower part of the second bracket.
According to such a prior art, at the time of an automobile crash, the rear-end upper part of the second bracket is removed from the vehicle body-side member and makes a backward turn around the pivotally attached position. As a result, the lower part of a brake pedal moves forward, preventing the brake pedal from moving back. Thereby, a crash load can be prevented from being laid on the driver's foot. In addition, the compressed spring which promotes the backward turn of the second bracket is disposed in a compressed state, so that the second bracket can be turned without fail by the force of the compressed spring.
Furthermore, Japanese Patent Laid-Open No. H11-139346 specification is configured by comprising: a first pedal bracket fixed on a first vehicle-body component member; a second pedal bracket, a vehicle-used pedal being pivotally attached to the second pedal bracket so that the vehicle-used pedal can swing, the front-end side of the second pedal bracket being supported on the first pedal bracket so that the second pedal bracket can swing, and the rear-end side of the second pedal bracket being fixed on a second vehicle-body component member at a more vehicle rearward-side than the first vehicle-body component member, the second vehicle-body component member being more rigid than the first vehicle-body component member; and a guide member for displacing the rear end of the second pedal bracket toward the vehicle lower-side at the time of an automobile crash.
According to such a prior art, at the time of an automobile crash, the rear end of the second pedal bracket is removed from the second vehicle-body component member and makes a backward turn around the pivotally attached position. As a result, the lower part of a brake pedal moves forward, preventing the brake pedal from moving back. Thereby, a crash load can be prevented from being laid on the driver's foot. In addition, the guide member for displacing the second pedal bracket toward the vehicle lower-side is provided, so that the second pedal bracket can be displaced without fail toward the vehicle lower-side.
However, the above described former prior art is configured so that the compressed spring promotes the turn of the second bracket, and thus, you have to set the force of the compressed spring. This presents a disadvantage in that if the set force is too weak, then the compressed spring will not be able to promote the turn of the second bracket adequately. On the other hand, if it is too strong, then the compressed spring will keep exerting its turn-promoting force on the second bracket and also on the driver's foot, affecting the driver's regular braking operation.
According to the above described latter prior art, the guide member for displacing the second pedal bracket toward the vehicle lower-side is configured by a slide plate attached firmly to an instrument-panel reinforcement behind the operation pedal. Herein, the instrument-panel reinforcement is located away from the operation pedal. This makes it difficult to allow the second pedal bracket to come into contact with the slide plate and be displaced toward the vehicle lower-side. The instrument-panel reinforcement or the slide plate attached firmly to the instrument-panel reinforcement of larger size is required to solve the problem.
In consideration of the aforementioned problems, it is an object of the present invention to provide an automobile pedal supporting structure, which is capable of preventing the operation pedal from moving back by ensuring a turn of the operation pedal, without affecting the driver's pedal operation and with keeping the vehicle body from becoming larger.